My wife and I are making the trip from the DC area again this year. This will be our third time making the 4 hour drive to Morgantown. As everyone else has said, it's a great road game to attend. Reminds me a lot of being in Ames at JTS. We usually just make it a day trip, so can't help as much with hotels/bars etc.
I did want to mention, if you want to get tickets in the ISU visitor section, we get ours through the DC chapter of the alumni association. It's a lot more fun than being random ISU fans surrounded by WVU fans. Two years ago we actually sat right behind Joe Scates' mom and family and he caught his first collegiate TD in the second half. It was really cool celebrating with them - actually one of my favorite moments I've had at any ISU sporting event.